1. Field of the Invention
The present invention relates to an image display method for displaying digital image data on a television monitor screen.
2. Description of the Related Art
Following start of digital high-vision broadcasting, television receivers for digital high-vision have spread widely, thus enabling users to enjoy higher-quality and more impressive videos at home than before. Further, electronic still cameras have spread, so that users have increasingly displayed and enjoyed electronic still images and moving images not only on screens of personal computers but also television monitor screens.
To view still images or moving images using a television receiver, a user normally looks at a list of thumbnail images displayed on a television monitor screen, selects one of the thumbnail images, and thereby selects data to be reproduced.
Meanwhile, memories with rapidly increased storage capacities have recently been available. The number of images to be stored is increasing by leaps and bounds, accordingly. A memory card, for example, can store over 500 digital photographs.
It has been difficult for the user to find desired data from among image data in large quantities.
Examples of a technique for efficiently arranging large quantities of data objects on the monitor screen, and for enabling the user himself or herself to easily select one of the objects with user's own eyes include a technique for moving thumbnail images while overlapping them, and for facilitating finding desired data as disclosed in Japanese Patent Application Laid-Open (JP-A) No. 2001-306375. They also include a technique, disclosed in JP-A No. 9-259130, for displaying image data in a three-dimensional space, moving a virtual eye view, and thereby finding desired data.
The conventional techniques have, however, the following disadvantages. Since the thumbnail images are displayed while being overlapped with the other thumbnail images, important parts for discrimination of photographs are often hidden. A photograph A and a photograph B are present, for example, as shown in FIGS. 14A and 14B. In the photograph A, children who are “running in a race” on the left of the image is an important part. In the photograph B, a person on the right of the image is an important part. If these photographs A and B are displayed while being overlapped with the other photographs, the photographs A and B are displayed with their important parts hidden as shown in FIG. 14A.
To prevent them, as proposed in the JP-A Nos. 2001-306375 and 9-259130 stated above, there is no other choice but for the user to carry out operations such as scrawling of the displayed image or moving a position of a virtual eye view so as to be able to view the important part of each photograph, and then to discriminate the photograph.
The present invention has been achieved in light of the conventional disadvantages. It is an object of the present invention to provide an image display method which enables a user to easily find a desired image while large quantities of images are efficiently arranged on a monitor screen.
Further, each of almost all photographed digital images can be divided into a region which a photographer regards as a subject and the other region. The former region will be referred hereafter to as “region of interest” and the latter region will be referred to as “region of no interest”.
If an operator of an image display apparatus is to search a desired image from large quantities of digital images, it is considered that the operator determines the desired image based on the region of interest in each of the digital images.
Conventionally, to create a thumbnail image, image data is uniformly reduced without discriminating the region of interest from the region of no interest. Due to this, when a plurality of images are displayed as a list of thumbnail images, the regions of interest in the respective images are displayed in small sizes. As a result, it is disadvantageously difficult to find a desired image based on the regions of interest as criteria of determination while looking down on the large quantities of digital images.
Considering the disadvantage, a method for detecting a face area in an image, enlarging the detected face area, and displaying a thumbnail image in a list is proposed, as disclosed in JP-A No. 2002-358522. According to this method, a system having an improved performance for searching a desired digital image can be realized by detecting the face area as the region of interest, enlarging the detected face area, and displaying the enlarged region.
With this method, since the list of thumbnail images is displayed with the respective regions of interest enlarged, the number of images which can be displayed once on the monitor screen is fixed in advance. Due to this, if the number of images exceeding the fixed number of images which can be displayed once on the monitor screen, such functions as a scrawling function and a function of turning over pages are additionally required, thereby disadvantageously complicating user's operation.
In addition, if both enlarged regions of interest and original images are displayed as thumbnail images, the number of images which can be displayed once on the monitor screen is disadvantageously, further reduced.
If the face area cannot be detected from a target image, no measures can be disadvantageously taken.